Ciao waldiamiga, which screen video and ROM you have chosen? I used that as a ROM file from 1,85 MB (1.945.746 byte), and that from 2,66 MB (2.796.822 byte) well accepted but black screen; for the video card I tried both CGX che P96 resolution 800x600.

Use Rom with Mac OS 8.6 (1 945 332 bytes), and depending on the number of colors I have a gray screen (1 bit) or black (8 bit). The emulator starts up you see.
Sorry for my english